Just swapped out my injector pump with a remanufactured unit(1 year warranty from Nerings). I got it all timed right, back together, and fired it up. It started right up and idled smooth at 1000rpm, then it dropped and started misfiring and shaking for a couple minutes, then it would smooth out again for a bit, then miss. Is this due to idle relearn? It would even out again if the rpms were brought up to 1200 or so. Also discovered a fuel leak...looks like from the return off the pump but I'm not 100% certain yet. Would the rough running and fuel leak be related? Any ideas would be great...I'm about ready to throw a match at it😖

I'm pretty sure that it's a bad injector. I think getting the pump issues sorted out...it has made injectors issues more prevalent. It seems the knock or misfire happens only at idle now. On the road above 1700rpm it runs great and has tons of power compared to before, also no more idle hunting.
I'll try and post a YouTube link.

Just in case you are about to go off on a tangent with this problem, I’m throwing this comment in. A couple of years ago my pump was rebuilt – I am lucky to have a firm nearby that specialises in these pumps. At the time I asked them about the injectors as I’d done just on 300,000km. and I was told to forget about them as they should be good for at least 500,000km.

From what I can gather, these pumps need specialised equipment to set them up correctly – there are only 3 places in the whole of Australia who rebuild them. You may find you will need someone to tune the pump once it is on the vehicle.

When I first got mine back I noticed it was blowing a bit of smoke when I started the motor. I asked about it and the chap said they tune the pump like that (extra fuel on start I think he said) as the pumps tend to lean themselves out a bit as they wear in. I’ve noticed it doesn’t blow smoke like that anymore.

Whelp...its definitely an injector. I put a used set from a friend near me surprisingly that had some. They were of unknown condition. I swapped them all out but organizing my own by corresponding cylinder. With the used set it ran even worse...knocked worse, wouldnt rev past 2000rpm, LOTS of smoke. I put my own back in in the proper order...same knock, some smoke, would even out above 1700rpm, and rev almost to 4000rpm. I let it run and warm up, then I used a infared thermometer gun pointed at the exhaust manifold at each port...most were around the 165-180F range. The rear one was the warmest(that's closer to the exit). #2 was more like 120F. I then used an automotive stethoscope to listen on the intake side. Guess what?...#2 sounded considerably different...more "clanky". So, out of the 4 spares I have, I'm going to swap them with #2 one by one until I get a good one...tedious, but my only option until I order them and they arrive. A stop gap to get me going for now. 1 of the spares has to be good hopefully, otherwise it wouldnt have ran at all.🤞

Whelp...its definitely an injector. I put a used set from a friend near me surprisingly that had some. They were of unknown condition. I swapped them all out but organizing my own by corresponding cylinder. With the used set it ran even worse...knocked worse, wouldnt rev past 2000rpm, LOTS of smoke. I put my own back in in the proper order...same knock, some smoke, would even out above 1700rpm, and rev almost to 4000rpm. I let it run and warm up, then I used a infared thermometer gun pointed at the exhaust manifold at each port...most were around the 165-180F range. The rear one was the warmest(that's closer to the exit). #2 was more like 120F. I then used an automotive stethoscope to listen on the intake side. Guess what?...#2 sounded considerably different...more "clanky". So, out of the 4 spares I have, I'm going to swap them with #2 one by one until I get a good one...tedious, but my only option until I order them and they arrive. A stop gap to get me going for now. 1 of the spares has to be good hopefully, otherwise it wouldnt have ran at all.🤞

Good luck. Keep us updates with how your progressing..

__________________Dicko FNQ

2014 NW with all the usual stuff plus more.Why is lemon juice made with artificial flavouring, and dish washing liquid made with real lemons?.

Yes I did valve clearances when I got it a couple months ago.
I'm starting to think it's not injectors. One thing I notice is that when I start it up right after the battery has been disconnected, it runs great for 45 seconds...then it starts to slope and knock. I wonder if it has something to do with pump timing adjustment. Like it runs good until the computer figures out timing or something, then it tries to adjust. It doesnt look fun to get at thise 3 bolts to turn the pump. There were 2 hash marks on the housing...perhaps the wrong one was chosen. I had to swap my front housing/gear assembly on to the new pump. I am 100% certain the teeth were lined up correctly though.
This thing is giving me angina...lol

take the boost pipe off and check that the throttle body is not choking it at idle.

- the throttlebody closes about 95% (once up to temp) at idleto make the idle smoother. If the adjustment is bad it can choke and splutter.

I checked...its wide open.
When its idled up to ~1400rpm and warm, I crack the feed pipes and there is a definite change on #4 and #2...none on 1 and slightly on 3...so maybe those 2 injectors are sketchy. Maybe an injector problem is more apparent now with a new pump(a rebuild). But what doesnt make sense is why it runs fine and doesn't knock when I first start it after the battery is connected back up. Is it a computer or pump timing issue?..I hope not

I installed new injectors with new washers and O-rings, however the issues still exist to some degree.
When I hooked the battery back up, it fired up and ran smooth for minute or so then the shutter/knock came back and it was really smokey...white/light grey smoke...and it seemed like it was running on 2 cylinders.
I rested a block on the peddle so it ran at ~1000rpm. Eventually the smoke let up a bit but not much, and the fumes were stinging my eyes. When it was throttled up, the shutter seemed to go away. I let it warm up to operating temperature, gave it a couple good sharp pokes on the throttle...it seemed to snap right up to 35000rpm but struggled to rev higher. It did blow out a bit of smoke occasionally. I let it settled back down to idle and it seemed to run smooth for 15min or so until I shut it off. I let it cool down and restarted it about 40min later and the shutter and smoke were back.
The more research I do leads me to believe that the pump timing is off or retarded...hence to lack of power and white smoke/terrible fumes.
When I got the rebuilt pump, I had to install the front housing/gear section from my old pump on the new one. I am 100% sure the teeth are lined up correctly when I installed it...i was careful to make sure it was at TDC and i marked all the teeth. I was able to take a pic when it was installed and confirmed everything lined up. I think maybe the mark on my old pump and the mark on the housing of the new one dont correspond correctly with each other.
So I suppose now I will fight with those 3 nuts on the housing and try to rotate it a bit to see if the takes care of the rough idle and smoke.
I am still convinced that it's not an internal problem like a bearing or a cracked piston, or head gasket. Like i said...the clatter/misfire seems to be almost intermittent. If it was one of these problems, it would always be noisy or the exhaust would smell like coolant, etc.
I am getting frustrated however...new pump and injectors $$$$...but still not right.